The Rain Method

Date:Jun 28, 2019

Rain method is used to test the moisture resistance of fabric exposed to air when simulating heavy rain. This method is applicable to any fabric that has been or has not been water-repellent.

The impact water permeability of single or composite fabrics was measured under the impact strength of water at different speeds. The test results are related to the water-repellent properties of fibers, yarns and fabric structures. The principle is that the test sample is wrapped around the weighed absorbent paper, and after the test, the absorbent paper is weighed again. The difference in weight between the two samples is the water permeability of the sample. It is required that the quality difference before and after the test of absorbent paper should not exceed 1g; If the quality difference is greater than 5g, it means that the fabric is very poor in water resistance.

Rain shower tester was used in the experiment. AATCC 35-2006 test method was to place a standard absorbent paper of 15.2cm×15.2cm at the back of the sample, and weigh the standard absorbent paper with an accuracy of 0.1g. On the vertical rigid surface, the sample is clamped on the sample holder. The sample is placed in the middle of the spray, 30.5cm away from the nozzle. The water flow of (27±1)℃ is directly sprayed on the sample horizontally for 5min. After the spraying, carefully remove the absorbent paper and weigh it quickly, accurate to 0.1g. The weight increase of the absorbent paper within 5min spraying time was calculated and the average value of the test data was taken. If greater than 5.0g, it is reported as +5.0g or >5.0g.